The present invention relates to a chromatographic column.
Chromatographic columns are used for the separation of substance mixtures and are based on the use of the property of gases or liquids existing in specific sorption coefficients which manifest themselves in differing retention times. Of essential importance for a clear cut separation is the behavior of the liquids passing through the column. Since chromatographic separations are often carried out under pressure and changes in bed volume arise due to this pressure and other factors, inhomogeneities in the bed or between the bed and the upper part of the bed and the feed in the form of dead volume result, impairing a reproducible, straight front profile of the free-flowing media. Pressure losses have a similarly disturbing effect.
It is known to use seals in the form of rubber O-rings, which are laid on the upper rim of the column and squeezed by a cap screw joint, accommodating the supply and discharge lines, against the widened column ring bearing against the underside of the latter.
A disadvantage with the known chromatographic columns is that the nature of the screw joint does not allow a visual inspection either of the seal or of the transition of the liquid from the feed into the chromatographic bed, or of the liquid from the chromatographic bed into the feed.
Furthermore, the distance between bed surface and liquid feed cannot be satisfactorily bridged.